mmc: sdhci-sprd: clear the UHS-I modes read from registers

sprd's sd host controller supports SDR50/SDR104/DDR50 though, the UHS-I
mode used by the specific card can be selected via devicetree only.

Fixes: fb8bd90 ("mmc: sdhci-sprd: Add Spreadtrum's initial host controller")
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Signed-off-by: Chunyan Zhang <zhang.lyra@gmail.com>
Reviewed-by: Baolin Wang <baolin.wang@linaro.org>
Tested-by: Baolin Wang <baolin.wang@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-sprd.c

@@ -509,7 +509,8 @@ static void sdhci_sprd_phy_param_parse(struct sdhci_sprd_host *sprd_host,
 
 static const struct sdhci_pltfm_data sdhci_sprd_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
-		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK,
+		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
+		  SDHCI_QUIRK_MISSING_CAPS,
 	.quirks2 = SDHCI_QUIRK2_BROKEN_HS200 |
 		   SDHCI_QUIRK2_USE_32BIT_BLK_CNT |
 		   SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
@@ -614,6 +615,16 @@ static int sdhci_sprd_probe(struct platform_device *pdev)
 
 	sdhci_enable_v4_mode(host);
 
+	/*
+	 * Supply the existing CAPS, but clear the UHS-I modes. This
+	 * will allow these modes to be specified only by device
+	 * tree properties through mmc_of_parse().
+	 */
+	host->caps = sdhci_readl(host, SDHCI_CAPABILITIES);
+	host->caps1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
+	host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_SDR104 |
+			 SDHCI_SUPPORT_DDR50);
+
 	ret = sdhci_setup_host(host);
 	if (ret)
 		goto pm_runtime_disable;